fix(mobile): increase inline skill chip contrast in dark mode

Problem

In the mobile app's default dark theme, an inline skill token can render as white or near-white text on a light green/accent chip. The foreground and chip background are too close in luminance, so the skill name is difficult to read.

The composer token colors flow through --color-inline-skill-background, --color-inline-skill-border, and --color-inline-skill-foreground into the native Android composer editor.

Expected behavior

Inline skill names should remain clearly readable against the chip background in the default dark theme.

Acceptance criteria

• Use an explicit high-contrast foreground/background pairing for the default dark theme.
• Meet WCAG AA contrast for normal text (at least 4.5:1).
• Keep the skill chip visually distinct from file/mention chips.
• Verify the Android native composer token rendering.
• Include before/after Android screenshots.

Search for --color-inline-skill-background, --color-inline-skill-border, and --color-inline-skill-foreground, then trace how these tokens reach the native Android composer editor. Check the default dark theme pairing against WCAG AA and compare it with file and mention chips. Verify the Android rendering and provide before/after screenshots.